Stoker construction



Nov. 10, 1936. W, T, HANNA l 2,060,307

STOKER CONSTRUCTION Original Filed April 5, 1929 3 Sheets-Sheet l l NYENTOR ATTORNEY 5v Original Filed April 5, 1929 3 Sheets-Sheet 2 Nov. l0, 1936.

w. T. HANNA STOKER CONSTRUCTION Original Filed April 5, 1929 3 Sheets-Sheet 3 ATroRNEY 5 Patented Nov. 10, 1936 6 UNITED STATES PATENT OFFICE STOKER CONSTRUCTION William Thompson Hanna, Cincinnati, Ohio Original application April 5, 1929, Serial No. 352,760. Divided and this application August 1, 1930, Serial No. 472,347

6 Claims. (Cl. 110-101) This invention relates to stokers in general end of the conduit I6 is provided with a universal but more particularly to stokers for use on lococonnection with the extension I4 below the deck motives and the like. |I of the locomotive. This connection comprises One of the objects of the invention is to proa spherical shaped member I6a secured to the vide a simple, compact and sturdy Stoker mechend of the conduit IB and journaled in a spher- 5 anism which will effectively convey the fuel ical shaped recess I4a in the end of the extenfrom the coal hopper in the tender to the re sion |4.

box of the locomotive and insure proper dis- The conveyor i5 has an operative connection tribution of the same therein. (not shown) with a conveyor I8 mounted for ro- 10 Another object is to insure free movement of tation within the tender hopper |9 below the 10 the fuel throughout the Stoker mechanism. tender deck 2U. The conveyer I8 in turn is Another object of the invention is to provide operatively connected with a power device 2|, a stoker mechanism of the character above delocated on the locomotive and this connection scribed in which there is an improved operacomprises a telescopic shaft 22, universally contion, and which is more effective to spread the nected at 23 with the power device and at 24 15 fuel more evenly over the fire bed of the fire box. with a shaft 25. This shaft 25 is journaled upon Other objects will be in part obvious and in the tender hopper and has at its rear end a gear part pointed out hereinafter. (not shown) which meshes with a gear 26 This application is a division of my copend- (shown in dotted lines) secured to the rear end ing application Serial No. 352,760, iiled April 5, of the conveyer I8. 20 1929, now issued into Patent No. 1,961,215. The contour of the housing I3 and its exten- The invention accordingly consists in the feasion I4 is designed to receive the fuel from the tures of construction, combinations of elements delivery end of the conveyer l5, and to elevate and arrangements of parts which will be exit in a substantially direct line of iiow from the empliiied in the mechanism hereinafter demouth 31 of the extension |4 to the firing open- 25 scribed and the scope of the application of which ing I2. In other words, there is an alignment will be indicated in the following claims. between the mouth'3'I and the firing opening I2.

In the accompanying drawings is shown one This straight line of ow has many advantages, of the various possible embodiments of the insuch as increasing the efficiency of the stoker 0 vention in which: mechanism by increasing the ease and freedom 30 Fig. 1 is a side elevation partially in section; with which the fuel moves through the hous- Flg. 2 is an enlarged longitudinal sectional ing I3.

view of the portion of the stoker mechanism ad- This freedom of flow is further enhanced by jacent the fire box but with the fuel propelling the particular construction of the extension |4.

or conditioning devices removed from the The cross-section of the housing extension I4 35 housing. and the cross-section of the housing I3 where it Fig. 3 is a sectional view on the line 3-3 of joins the extension I4 as at 31 is substantially Fig, 2; circular in contour, thus giving, in effect, a cir- Fig. 4 is a sectional View on the line 4-4 of cular conduit through which the fuel is elevated 40 Fig. 2; to the ring opening I2. The cross-sectional 40 Fig. 5 is an ideal section of the fuel propelling area of the extension I4 is the smallest at that and conditioning device of Figure 3, taken on portion designated |411, this portion being subline 5-5 of Figure 3; and stantially of the same diameter as the inside Fig. 6 is a transverse view on the line 6-6 diameter of the member |62. Immediately forof Fig. 2. ward of the point I4", the extension I4 is sud- 45 Referring to the drawings, I0 represents the denly enlarged on the top half thereof as shown back head of a locomotive fire box having the in Figs. 2 and 6. This feature serves to give the usual grate bars and firing opening I2. Emvolume of fuel a sudden relief as it begins its bracing this opening and rigidly mounted on the upward movement through the conduit and very outer face of the back head l0 is a fuel supply materially facilitatesthe elevation of the fuel. 50 housing |3 having, at its lower end, a fuel sup- Further, the cross-sectional dimension of the conply conduitor extension |4 merging therewith. duit forward and upward from the point I4b has This extension encompasses the delivery end of an increasing diameter which, in effect, gives the a transfer conveyor I5 which is rotatively supupper end of the fuel supply conduit a flaring, as

ported in a cylindrical conduit |6. The. forward shown at 31. 55

To further assist in the freedom of ow of the fuel through the housing I3 there are provided in the walls of the housing I3 fuel supporting recesses or conically shaped ledges 33 which, as shown in the present embodiment, slope forwardly and upwardly toward the firing opening I2. For purposes to be described hereinafter, the fuel supporting recesses 33 are conically shaped and converge to the apex of the imaginary cones embracing the recesses pointing toward the firing opening I2. The forward ends 33b of the recesses 33 meet at a point 38 just in the rear of the lower edge of the firing opening I2. The forward and upper portion of the mouth 37 also meets the two ends 33b at point 38. The mouth 37 of the extension I4 intersects or merges with the recesses 33 along edges 33a, as shown more clearly in Figures 3 and 4. The combination of the flaring mouth section 37 of the extension I4 with the edges 33e and the recesses 33 provides many new and highly advantageous results. For example, a rising column of fuel in the extension I4 is allowed to expand toward the sides of the housing I3 over the flared mouth 37 whence it spills over the edges 33a, and drops on to the fuel supporting recesses 33. In this way, any tendency of the fuel to mound or pile up in front of the center of the firing opening I2 is offset, and thus the back pressure upon the rising column of fuel, caused by excessive mounding of fuel thereof, is eliminated.

To further expedite the even, uninterrupated and distributed flow of fuel from said fuel supply housing through the firing opening I2, I provide in the housing I3 fuel spreading or fuel conditioning means 27 and 28 respectively, each means comprising, in the present embodiment, a rotatable spiral tapered vane or worm. Each worm 27 and 28 is positioned in its respective recess 33, and suitably journaled in cap-plate 29 or 38, forming part of the wall of the housing I3. The recesses 33 are so constructed, and their respective rotary vanes 27 and 28 so positioned, that the portions of the recesses or ledges 33, generally indicated at 39, which are remote from the firing opening I 2, are curved to conform with a conically shaped surface containing the outer periphery of the respective vanes 27 and 28. However, those portions of the recesses 33 adjacent the edges 33a are curved eccentrically about a surface containing the outer periphery of the vanes, as shown in Figure 5. By providing this eccentricity between the vanes 27 and 28 in their respective recesses 33, fuel that flows over the edges 33Z1 on t0 the ledges 33 from the extension I4 cannot jam between the hub of the vane and the surface of the ledge, but readily passes on around.

With the construction shown in the present embodiment I find it particularly advantageous to position the axes of the vanes 27 and 28 so that the vanes converge laterally and upwardly toward the center line 38 at the lower edge of the ring opening I2. Under certain conditions of operation, however, I may nd it advantageous to arrange the axes in a parallel arrangement with respect to each other, or in an arrangement whereby the axes diverge from each other.

Rotary motion is imparted to the vanes 27 and 28 through suitable gearing, (not shown) within the housing I 3, and driven by the telescopic shafts 32 which are universally connected each at one end with such gearing and at the other end with the power device 2I, or in any other manner that may be found most expedient.

'I'he fuel propelling and conditioning mechanism, comprising the spiral vanes 27 and 28, has associated therewith a blast chamber 34 and a distributing plate 35 lying within the firing opening I2 and these serve to scatter the fuel efficiently to all parts of the nre bed. The tender hopper i9 is equipped, at its delivery end, with a powerful fuel crushing device 36.

In the operation of this stoker mechanism the coal passes through the deck 20 of the tender into the trough of the tender hopper I9 and is moved therein by means of the conveyer I8, into the crushing device 3G wherein the abnormally large lumps of fuel are cracked and broken up to normal size before discharge from the tender hopper. The fuel is then delivered to the transfer conveyer I5 by which it is transported and delivered into the ascending conduit formed by the housing extension I4 and the lower portion of the housing I3. mouth portion 37 of the extension Ill, still being pushed on by the oncoming fuel beneath, tends to fall away at the sides due to the flaring at the mouth 37 and flows over the edges 332L on to the recesses 33 where it encounters the vanes 27 and 28 which serve to disintegrate and spread the rising column of fuel over the fuel conditioning housing I3 and cause the loose fuel to pass through the firing opening in a continuous uniform stream and fall upon the plate 35. It is then scattered over the fire by means of blasts of steam emitting from the jets of the blast chamber 34.

It will be recognized that the form of the passage through which the fuel is elevated to the vanes 27 and 28 is such, the said passage on the right hand and left hand sides, that the rising column of fuel is permitted to spill over into the path of the outer ends of the vanes and the effect of this is to decrease the tendency of the fuel to mound or pile up at the center in front of the vanes as might be the case with certain conditions of fuel. Furthermore, it is evident that the relationship between the surface of each ledge 33 and its respective vane is such that the spacing between the ledge and vane gradually increases from the edges 338 of the ledge around to the forward part thereof as generally indicated at 40, Figure 5. With this construction tendency of lumps of fuel to become wedged between the hub portion of the vanes 27 and 28 and their respective ledges, or be: tween the outer peripheries of said vanes and their respective edges is avoided.

It will thus be seen that there is provided a construction of an essentially practical nature in which the several objects of the invention are attained.

While I have shown and described a particular construction embodying the novel features of the invention, it is to be understood that the same is for illustration only and it will be obvious that the construction and arrangement of parts may be variously modified and altered without departing from the spirit and scope of the invention as set forth in the appended claims.

I claim:

1. In a stoker mechanism, the combination with a re box having a fuel entrance of a housing embracing the fuel entrance and formed to provide a ledge in the rear of the fire box opening to receive fuel delivered thereto, and a spiral vane rotatably mounted in the housing and extending over the ledge to break up the fuel delivered to the ledge and feed it to the fire box, the portion 0f the ledge remote from the re box being curved At this point the fuel in the particularly at the top of to conform to the periphery of the spiral vane, and the portion of the ledge adjacent the nre box being curved eccentrically to the' periphery of the spiral vane to facilitate the feeding of the fuel to the re box, and means for delivering the fuel upwardly and over that portion of the ledge remote from the fire box.

2. In a stoker mechanism for a re box having a back head and a firing opening in said back head, in combination, a fuel conditioning housing communicating with said firing opening and having a fuel supply conduit opening thereinto, said fuel conditioning housing having a plurality of elongated concave fuel supporting recesses formed therein; and a plurality of fuel loosening screws mounted in said housing, each fuel loosening screw having its lower portion embraced by one of said recesses, at least a portion of the surface of each of said recesses being concentric with and parallel to a surface containing the outer surface of the fuel loosening screw located therein, and another portion of the surface of each of said recesses being curved eccentrically about a surface containing the outer surface of its respective fuel loosening screw whereby fuel entering between said fuel loosening screws and their respective recesses will not become wedged therebetween.

3. In a stoker mechanism, the combination with a locomotive fire box having a firing opening and a tender of a housing communicating with the firing opening, transfer mechanism arranged to convey fuel from the tender to the housing, a rotatable spiral vane mounted within the housing to receive fuel from said transfer mechanism, a portion of said housing below and rearwardly of said vane being in the form of a circular conduit, the diameter of which increases as it approaches the vane, the upper end of said conduit flaring immediately below said vane, and a concave ledge formed continuously with said conduit intermediate said conduit and said firing opening and embracing the lower side of said vane and being curved eccentrically about the side thereof adjacent the firing opening, whereby fuel passing upwardly through said conduit may flow onto said ledge into the radius of said vane.

4. In a stoker mechanism, the combination with a fire box having a fuel entrance, of a conduit provided with means for moving fuel from a source of fuel supply to said entrance and having a recessed fuel supporting ledge formed therein and positioned adjacent and to the rear of said entrance, means for distributing fuel fed to said entrance upon and over the nre, and fuel conditioning and regulating means comprising a rotary worm associated with said conduit and fuel entrance and interposed between said fuel moving means and said distributing means for moving fuel across the fuel supporting ledge to transform the forced fuel into form relatively thinner than the bulk of fuel in the conduit and to regulate the presentation of fuel to the distributing means, said rotary worm being positioned in part in said recessed ledge, and the ledge being curved eccentrically with respect to the periphery of the rotary worm to provide increasing space between the periphery and surface from the point where fuel first moves onto the surface to the point where it leaves the surface.

5. In a stoker mechanism in combination a fire box having a firing opening, a fuel transfer conduit for conveying fuel from a source of supply to said firing opening, a curved recessed fuel supporting surface in said conduit and extending crosswise thereof over which fuel flows in passing to said firing opening, and a conically shaped rotatable fuel moving worm mounted in said conduit above said fuel supporting surface and extending into the recessed portion thereof to move fuel thereacross to said firing opening, and the space between the outer periphery of said rotary worm and said surface constantly increasing from the point where fuel first moves onto said surface to the point where the fuel leaves said surface whereby the possibility of fuel becoming wedged between said worm and surface as it moves thereacross is eliminated.

6. In a stoker mechanism, the combination with a fire box having a firing opening, of a housing communicating with said opening and having a fuel supply inlet, said housing also having an elongated concave fuel supporting recess formed in a wall thereof and generally sloping upwardly toward said ring opening; a tapered spiral vane rotatably mounted in said housing and positioned in part in said recess, the portion of said recess remote from said fire box being curved to conform to a surface containing the periphery of the spiral vane and the portion of the recess immediately adjacent the re box being curved eccentrically tothe surface containing the periphery of the spiral vane, and means for delivering the fuel upwardly and over that portion of the recess remote from the re box.

WILLIAM THOMPSON HANNA. 

